In numerous applications there is a need to perform sonar beamforming operations to acquire spatial information regarding a particular area of interest. Sonar systems make use of sensor arrays to process underwater acoustic signals to determine the location of a noise source. Array processing techniques for isolating received signals are known as beamforming and when the same or analogous principles are applied to focus the transmission of signals, the techniques are referred to as beamsteering. Various systems have been developed to perform such beamforming operations that frequently depend upon the particular applications.
One such application involves undersea search and survey that has various uses such as, but not limited to, terrain mapping and dredging operations. Further, undersea acoustic mine-field reconnaissance and mine hunting applications benefit from high-resolution imaging sonars for clutter rejection, obstacle avoidance, and identification of foreign objects. Currently, the discovery of underwater mines and obstructions is performed by touch in cold, murky water, often at night, under low-light conditions. Navy salvage, explosive ordinance disposal, and other military and civilian applications operate in zero-visibility water where “seeing with sound” using unmanned vehicles would make their jobs significantly more efficient and safer. Commercial applications which include, for example, commercial navigation or aiding search and rescue dive teams would benefit from an improvement in imaging systems.
There is still a need for a light-weight, low-power, low-cost, unmanned self-propelled sonar system for remote undersea imaging or surface imaging.